Earth anchor



25, 1964 K. R. WAY ETAL 3,145,812

EARTH ANCHOR Filed Oct. 31. 1960 INVENTORS KENNITH '2. MY IRYMOND M LCMFIG. 3 BY CZQMM ATTORNEYS United States Patent 3,145,812 EARTH ANCHORKenneth R. Way, Webster Groves, and Raymond N.

Leach, St. Louis, Mo., assignors, by mesne assignments,

to Jasper Blackburn Corporation, a corporation of Missouri Filed Oct.31, 1960, Ser. No. 66,223 3 Claims. (Cl. 189-90) This invention relatesto improvements in earth anchors for securing guy cables and the like,and has particular reference to an improved plate anchor.

The general object of the invention is to provide an improved anchor forguying heavy distribution and transmission structures, and one havinggreat holding strength for its size and weight and which is relativelysimple and inexpensive to manufacture.

Among the advantages of the present anchor are case and facility ofinstallation in either vertical or inclined machine bored holes, and ashape that conforms to the curved side surface of the hole so that itwill quickly come into full surface pressure contact with the adjacentearth when tension is applied. These features obtain a reduction increepage when the anchor is being set, and the elimination of spotloadings that tend to bend the anchor and impair its holding strength.

Other important advantages are an economical, wastefree use of the platestock from which the anchor body is fabricated, and provisions thatcounteract the normal tendency of anchors, when installed in verticalholes, to ski or creep upwardly when load forces of great magnitude areapplied.

A further important advantage of the present anchor is its tendency toremain stabilized in a normal position of optimum holding power and toresist forces that tend to unbalance and tilt it into a position ofreduced holding power.

The foregoing and other objects and advantages are achieved in theprovision of a dome-shaped anchor body formed in the present examplefrom a square blank of plate steel. Surrounding the dome is an up-turnedperipheral flange formed from the marginal portions of the metal blank.The corner portions of the blank remain on the finished product and arepresented as upwardly and outwardly diverging points or flukes. A tierod is detachably secured to the anchor body at the apex of the dome.

By reason of its rounded or bulbous shape the anchor is enabled to fitsnugly against the side surface of a cylindrical hole drilled in theearth to receive the anchor. When installed in a hole that is drilledvertically, a growing practice in electrical pole line installations,the load forces which are initially applied to the anchor actimmediately to bring the anchor into full surface pressure engagementwith the adjacent soil. The flukes formed by the corner portions act todig in and grip the undisturbed earth at the sides of the hole,preventing the anchor from side-slipping upwardly through the lesserresistant earth which has been replaced in the hole followinginstallation of the anchor. The domed shape of the body and therelatively high point at which the rod is attached thereto favorstability and a retention of the anchor in its normal position ofmaximum holding power.

The foregoing and other objects and advantages of the invention willmore clearly appear from the following detailed description of apreferred embodiment, particularly when considered in connection withthe accompanyin g drawing, in which:

FIGS. 1 and 2 are phantom views showing the anchor of the presentinvention installed in a vertical bore in the earth;

3,145,812 Patented Aug. 25, 1964 FIG. 3 is a perspective view of theanchor;

FIG. 4 is a sectional view, and

FIG. 5 is a fragmentary view showing the underside of the centralportion of the anchor body.

Referring now by numerals of reference to the drawings, the anchorhereof comprises a body part 10 and an anchor rod 11. The body part 10is formed from a square blank of steel plate stock. The major portion ofthe blank, inwardly of its edges, is pressed to concave-convex form,more particularly constituting the dome 12 which is preferably aspherical segment. The bottom periphery 13 of the dome 12 is circular inconfiguration. Its apex is provided with an opening 14 to accommodatethe lower end of the anchor rod 11.

Formed integrally with the dome is the deep drawn rim or flange 15 whichis inclined upwardly and outwardly. The flange 15 offers greatresistance to failure from folding. It produces an annular trough orchannel, V-shaped in cross-section, extending around the base of dome12, which conduces to a solid packing of the earth in the said troughand at the upper surface of the anchor body.

The flange 15 includes the four corner portions of the original blank,the corners extending upwardly and outwardly from the bottom periphery13 of spherical segment 12. They constitute flukes 16 for penetratingand gripping the earth at the sides of the bored hole, and otherwiseserve to increase the anchor surface eifective for resistingdisplacement.

A reinforcing plate 17 is welded to the underface of the apex portion ofdome 12, and welded to the bottom of reinforcing plate 17 is a nutretainer 20 in which a nut 21 is fixedly held. As is best seen in FIG.4, the nut 21 is retained in a position aligned with the rod opening 14so as to engage threadedly the lower end of rod 11 extending through theapex of spherical segment 12.

The anchor is installed in a hole which, in accordance with modernpractice, may be produced by a rotary drill. The bore is desirablyinclined so as to be at a right angle to the guy cable but for reasonsof ease and convenience anchor holes are frequency drilled vertically.The present anchor also lends itself to satisfactory installation ineither slanting or vertical holes, especially because of its domed shapeand anti-skiing provisions. In either arrangement a kerf 23 is cut inthe ground laterally from one side edge of the hole 22 to accommodatethe anchor rod. Following proper placement of the anchor assembly in theaforesaid openings, the earth is replaced and tightly compacted aboutthe anchor and rod.

The particular structure and formation of the dome 12 and the flangeportion 15 provide an anchor of great strength and stability. Uponapplication of a tensional force on rod 11, such force is effectivelyresisted by the plate structure 10. The flukes 16 penetrate the earth atthe sides of the hole and afford increased resistance to any tendenciesof the anchor to move laterally, due, for example, to unequal density ofthe ambient material at different sides of the anchor. The roundedconfiguration of the dome portion makes for great strength and enablesthe body to fit closely against the cylindrical surface of the boredhole. In such position it can quickly assume full load when tension isapplied, with minimum initial displacement or creepage.

It will appear that in the production of the anchor herein describedthere is practically no waste material. All portions of original blank,with the exception of the portion removed to form the central opening 14for the anchor rod, are advantageously utilized.

Although the invention has been described by making detailed referenceto a single preferred embodiment, such detail is to be understood in aninstructive, rather than in any restrictive sense, many variants beingpossible within the scope of the claims hereunto appended.

We claim as our invention:

1. An earth anchor comprising a substantially square plate having cornerportions, the square plate being formed to provide a rounded dome-shapecenter portion and a flange portion extending upwardly from the bottomperiphery of said center portion, the flange portion including upwardlyprojecting tapered flukes constituted by the corner portions of thesquare plate.

2. In an earth anchor a body formed from a square sheet metal platehaving corner portions, said body comprising a rounded dome-shapedcenter portion, an annular flange projecting upwardly and outwardly fromthe bottom periphery of said center portion and constituting the outerwall of an annular trough, said flange including circumferentiallyspaced, upwardly projecting flukes constituted by the corner portions ofthe square plate, from which said anchor body is formed, and an anchorrod secured to said body at the apex of its dome-shaped central portion.

References Cited in the file of this patent UNITED STATES PATENTS2,002,628 Chance May 28, 1935 2,525,890 Gage Oct. 17, 1950 2,905,288Rnnde Sept. 22, 1959 3,012,643 Ridgers Dec. 12, 1961 FOREIGN PATENTS138,115 Switzerland Apr. 16, 1930

1. AN EARTH ANCHOR COMPRISING A SUBSTANTIALLY SQUARE PLATE HAVING CORNERPORTIONS, THE SQUARE PLATE BEING FORMED TO PROVIDE A ROUNDED DOME-SHAPEDCENTER PORTION AND A FLANGE PORTION EXTENDING UPWARDLY FROM THE BOTTOMPERIPHERY OF SAID CENTER PORTION, THE FLANGE PORTION INCLUDING UPWARDLYPROJECTING TAPERED FLUKES CONSITUTED BY THE CORNER PORTIONS OF THESQUARE PLATE.